The present disclosure relates to a lateral bipolar junction transistor (BJT) structure, and particularly to a germanium lateral bipolar junction transistor and methods of manufacturing the same.
Germanium-on-insulator (GeOI) lateral bipolar transistors have been demonstrated to achieve the same drive current as similar devices built on silicon/germanium on insulator (SiGeOI) and silicon on insulator (SOI) substrates at >400 mV lower of operation voltage, implying potential benefit in power-efficient applications. However, the current gain is limited by the excessive base current as compared to the SiGeOI and SOI devices. Analysis indicates the less-than-ideal base current in GeOI lateral bipolar transistors is likely due to the defects at the Ge/BOX interface. GeOI wafers with good passivation of the Ge/BOX interface is then required to fully utilize the benefit of GeOI bipolar transistor.